RICCI
Changes.txt
The list below shows all significant changes made to the package since the
first beta release.
3/10/16 Version 1.61:
Fixed bug in BasisExpand[Del[w]]
Fixed display of Del[w]
Fixed "shadow symbol" problem with new system symbols
Fixed bug in BasisExpand[tensor^p]
3/5/16 Version 1.6:
Fixed protection errors caused by new system symbols in Mathematica 9 & 10.
9/16/11 Version 1.53:
Fixed protection error caused by new system symbol
PermutationOrder.
8/28/06 Version 1.52:
Added code to correctly handle derivatives of conjugates of
math functions.
Corrected a sign error in CurvToConnRule (which only occurred
when RiemannConvention was set to SecondUp, the default).
6/28/04 Version 1.51:
Corrected errors introduced by Mathematica version 5.0:
* It now treats new system symbols (Norm,TensorQ,Variance)
correctly, so as to avoid protected symbol error messages.
* Fixed a bug in parenthesization of tensor expressions that
cropped up in Version 5.
11/12/02 Version 1.37:
Fixed a bug in Grad[u v, Metric->g]: When u is a 0-tensor,
the non-default metric was ignored when applying Grad to v.
7/26/02 Version 1.36:
Fixed a small bug in the evaluation of covariant derivatives
of mathematical functions such as Log[u+1][L[i]].
12/18/00 Version 1.35:
Fixed a serious mathematical bug in the evaluation of
Del[x,Connection->y] (which also affected the use of Del
with the Metric option, as well as other functions such
as Div with non-default metrics & connections). The problem
was that for a contravariant tensor v, the old version of
Ricci interpreted Del[v,Connection->y][L[i],L[j]] as if the
index of v had been lowered before taking the covariant
derivative, whereas to be consistent with Ricci's other
conventions it should have been lowered after.
1/7/00 Version 1.34:
Minor fixes to allow Ricci to work with Mathematica 4.0:
Treated Tr as a system symbol, with Protect/Unprotect
around definitions;
Replaced Literal by HoldPattern throughout.
6/30/99 Version 1.33:
Fixed the TangentBundle function so that it always assumes
$DefaultTangentBundle for "generic" tensors whose bundle
is denoted "Any". This allows BasisExpand to work correctly
with expressions such as Del(Tor.X).
1/2/98 Version 1.32:
Fixed bug in parenthesizing output expressions
8/18/97 Version 1.31:
Fixed bug inserting indices in Del[x,Connection->c]
2/11/97 Version 1.3:
Minor modifications to enable use with Mathematica 3.0.
4/19/95 J. Lee (Version 1.2.1)
* Corrected omission of usage messages from released version.
4/14/95 J. Lee
* Version 1.2 released.
2/17/95 J. Lee
* Made tensor simplification functions return Null if called in
error with no arguments.
12/29/94 J. Lee
* Corrected DefineConstant[x,Type->Positive]
12/14/94 J. Lee
* Fixed incorrect handling of Del[x,Metric->g] and Div[x,Metric->g]
* Rewrote the algorithm for TensorExpand to make it much faster on
expressions involving many factors.
7/11/94 J. Lee
* Make DefineRelation omit 1-dimensional bundle indices from the
list of dummy variables in its Module.
7/7/94 J. Lee
* Correct handling of dummy variables in the Module created by
DefineRule and DefineRelation.
7/1/94 J. Lee
* Make Kronecker[L[z1],U[z2]] = 1 for 1-dimensional bundles.
5/31/94 J. Lee
* Corrected code for Alt and Sym to correctly handle symmetric
products of tensors on 1-dimensional bundles.
3/23/94 J. Lee
* Added rules for Conjugate[RiemannTensor], Conjugate[RicciTensor],
and Conjugate[ScalarCurv].
11/25/93 J. Lee
* Fix bug in DefineBundle.m in processing of BasisName.
9/27/93 J. Lee
* Change all Ricci filenames to have no more than 8 characters, for
compatibility with DOS.
7/15/93 J. Lee
* Change DefineRule and DefineRelation so they create a "Module"
for each rule or relation defined; this prevents conflicts with
user-defined indices such as i1, i2, etc.
2/25/93 J. Lee
* Fixed bug in Dot that did not allow use of Mathematica's internal
Dot function for lists.
* Fixed bug in DefineBundle that didn't correctly set components of
the metric on a 1-dimensional bundle to 1 when OrthonormalFrame
-> True.
* Made metric components -1 when OrthonormalFrame -> True and
PositiveDefinite -> False on a 1-dimensional bundle.
2/12/93 J. Lee
* Fixed bug in InsertIndices that caused incorrect error message
when wrong number of indices is inserted into a tensor.
8/24/92 J. Lee
* Version 1.0 released.
8/21/92 J. Lee
* Added "CurvToConnRule".
* Added "CommutingFrame" option for DefineBundle.
* Changed interpretation of Type option for DefineConstant,
DefineMathFunction, DefineTensor: these functions now accept
Type->{Positive,Real} etc. instead of Type->PositiveReal.
* Added "Declare".
* Eliminated "CorrectVariances", and replaced it with the
Mode->OneDims option of "CorrectAllVariances".
* Changes the OneDims->False option of AbsorbMetrics to
Mode->NoOneDims.
8/13/92 J. Lee
* Added "ConnToMetricRule".
* Made UndefineBundle automatically undefine the Riemann, Ricci,
and Scalar curvature tensors when undefining a Riemannian tangent
bundle.
8/12/92 J. Lee
* Fixed various bugs relating to non-default metrics and
connections on a direct sum of bundles.
8/8/92 J. Lee
* Fixed BasisGather so it recognizes both x and -x. This is
necessary for expressions like ExtdStar[w] which begin with a
minus sign.
8/6/92 J. Lee
* Added rules to compute derivatives of components of inverse
tensors and inverse metrics in terms of the original tensor or
metric.
* Added code to make the inverse of a Hermitian tensor also behave
as a Hermitian tensor.
7/30/92 J. Lee
* Added the CommutingFrame option for DefineBundle
7/13/92 J. Lee
* Corrected sign bug in insertion of indices into RiemannTensor[g]
7/12/92 J. Lee
* Corrected bug in insertion of indices into Sym[_] and Alt[_]
7/8/92 J. Lee
* Added code to correctly handle Mma's builtin constants
7/7/92 J. Lee
* Ricci Version 1.0 Beta 1 released
This first beta release incorporated numerous changes from previous
versions, formerly called DG. The most important were:
* Change in syntax for DefineRelation and DefineRule: underscores
no longer used in dummy index names.
* Name changes: Tprod changed to TProd, Extdstar to ExtdStar, to be
more consistent with Mathematica's and Ricci's naming
conventions.
* Delstar has been replaced by Div, and CovLaplacian has been
replaced by Laplacian.
* Many new functions and options added, such as ProductExpand,
CovDExpand, SuperSimplify, BasisName, OrthonormalFrame,
ParallelFrame.